To improve the tracking stability control of unmanned surface vehicles (USVs), an intelligent control algorithm was proposed on the basis of an optimized radial basis function (RBF) neural network. The design process was as follows. First, the adaptation value and mutation probability were modified to improve the traditional optimization algorithm. Then, the improved genetic algorithms (GA) were used to optimize the network parameters online to improve their approximation performance. Additionally, the RBF neural network was used to approximate the function uncertainties of the USV motion system to eliminate the chattering caused by the uninterrupted switching of the sliding surface. Finally, an intelligent control law was introduced based on the sliding mode control with the Lyapunov stability theory. The simulation tests showed that the intelligent control algorithm can effectively guarantee the control accuracy of USVs. In addition, a comparative study with the sliding mode control algorithm based on an RBF network and fuzzy neural network showed that, under the same conditions, the stabilization time of the intelligent control system was 33.33% faster, the average overshoot was reduced by 20%, the control input was smoother, and less chattering occurred compared to the previous two attempts.

A novel polymer electrolyte is prepared by in-situ polymerization for lithium metal batteries. The polymer electrolyte with in-situ polymerization can maintain good inter-facial contact property between the electrodes and electrolyte....

At 2:37:34 seconds on April 14, 2017, a large area of the Qing Zone suffered a power outage. During the troubleshooting of the power Supply Bureau, it was found that there was a suspicious self-unloading vessel, " HXX 338," anchored in the anchor forbidden area of the submarine cable and weighed anchor. Hainan Power Grid sued the suspicious ship and won the lawsuit, but the ship owner insisted on the ship not damage the submarine cable. The power grid entrusts the author as the maritime expert to make a professional judgment concerning the suspicion of this accident. The author makes use of navigation common sense: after anchoring, the position of the ship must be within the radius of the arc with the anchor position as the center of the circle, the length of the chain thrown out plus the sum of the distance between bridge and anchor chain hole; put in another way, if the ship's position is known after anchoring, the anchor position must be in a circle with the ship's position as the center of the circle, the length of the chain thrown out plus the distance between bridge and the bow's chain hole and as the radius. The trajectory of the ship was analyzed, and the suspicious ship was identified as the ship resulting in the accident. Investigate and analyze the facts of the ship in question moving in the prohibited anchor zone and hooked up submarine cables, find out the causes and distinguish the responsibilities. This article has explored an effective analysis for maritime investigation.

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